help geometry

How many sides has an equiangular polygon if the sum of its exterior angles is equal to the sum of its interior angles?​    

The sum of the exterior angles of any regular polygon is 360^o      

Therefore the sum of the interior angles of our polygon is 360^o    

That makes it a square, which has four sides    

I just recognized it when I saw it, but for a difficult problem, we could have used the formula.   

The sum of the interior angles of a polygon with 'n' sides is given by the formula: S = (n – 2) • 180^o.    

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